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1.
Sci Rep ; 14(1): 12239, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806565

RESUMO

Laser-driven dynamic compression experiments of plastic materials have found surprisingly fast formation of nanodiamonds (ND) via X-ray probing. This mechanism is relevant for planetary models, but could also open efficient synthesis routes for tailored NDs. We investigate the release mechanics of compressed NDs by molecular dynamics simulation of the isotropic expansion of finite size diamond from different P-T states. Analysing the structural integrity along different release paths via molecular dynamic simulations, we found substantial disintegration rates upon shock release, increasing with the on-Hugnoiot shock temperature. We also find that recrystallization can occur after the expansion and hence during the release, depending on subsequent cooling mechanisms. Our study suggests higher ND recovery rates from off-Hugoniot states, e.g., via double-shocks, due to faster cooling. Laser-driven shock compression experiments of polyethylene terephthalate (PET) samples with in situ X-ray probing at the simulated conditions found diamond signal that persists up to 11 ns after breakout. In the diffraction pattern, we observed peak shifts, which we attribute to thermal expansion of the NDs and thus a total release of pressure, which indicates the stability of the released NDs.

2.
Front Immunol ; 15: 1359738, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545110

RESUMO

Urinary tract infections (UTI) caused by carbapenem-resistant Enterobacteriaceae (CRE) are considered one of the most urgent health threats to humans according to the Centers for Disease Control (CDC), and the World Health Organization (WHO). A FimCH Vaccine expanded access study is being conducted in patients with a history of antibiotic resistant UTIs who are considered to be at risk for development of CRE UTI. This case series describes the clinical, safety and immunogenicity findings for four participants who received a FimCH four-vaccine series. Participants were followed for 12 months after administration of the fourth vaccine for safety, general health status and UTI occurrence. The study was later amended to allow additional follow-up of up to five years post vaccine administration to assess long-term health status, UTI occurrences and to obtain blood samples for anti-FimH antibody testing. In our population of 4 study participants, the number of symptomatic UTI occurrences caused by gram-negative bacteria in the 12-month period following peak anti-FimH antibody response were approximately 75% lower than the 12-month period preceding study enrollment. These results are consistent with the 30-patient cohort of a Phase 1 study with the same FimCH Vaccine. UTI occurrences increased during the long-term follow-up period for all 4 participants but did not reach the rate observed pre-vaccination. No new safety concerns related to the FimCH Vaccine were identified during long-term follow-up. This case series has clinical importance and public health relevance since it examines and reports on UTI frequency and recurrence following vaccination with the FimCH Vaccine in a high-risk population of patients with recurrent UTI. Additionally, participants described improved well-being following vaccination which was maintained in the long-term follow-up period.


Assuntos
Infecções Urinárias , Vacinas , Humanos , Antibacterianos/uso terapêutico , Enterobacteriaceae , Seguimentos , Infecções Urinárias/prevenção & controle , Vacinas/uso terapêutico
3.
Sci Adv ; 10(6): eadh5272, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38335288

RESUMO

Studies of laser-heated materials on femtosecond timescales have shown that the interatomic potential can be perturbed at sufficiently high laser intensities. For gold, it has been postulated to undergo a strong stiffening leading to an increase of the phonon energies, known as phonon hardening. Despite efforts to investigate this behavior, only measurements at low absorbed energy density have been performed, for which the interpretation of the experimental data remains ambiguous. By using in situ single-shot x-ray diffraction at a hard x-ray free-electron laser, the evolution of diffraction line intensities of laser-excited Au to a higher energy density provides evidence for phonon hardening.

4.
Magn Reson Med ; 91(4): 1314-1322, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38044723

RESUMO

PURPOSE: To demonstrate J-difference coediting of glutamate using Hadamard encoding and reconstruction of Mescher-Garwood-edited spectroscopy (HERMES). METHODS: Density-matrix simulations of HERMES (TE 80 ms) and 1D J-resolved (TE 31-229 ms) of glutamate (Glu), glutamine (Gln), γ-aminobutyric acid (GABA), and glutathione (GSH) were performed. HERMES comprised four sub-experiments with editing pulses applied as follows: (A) 1.9/4.56 ppm simultaneously (ONGABA /ONGSH ); (B) 1.9 ppm only (ONGABA /OFFGSH ); (C) 4.56 ppm only (OFFGABA /ONGSH ); and (D) 7.5 ppm (OFFGABA /OFFGSH ). Phantom HERMES and 1D J-resolved experiments of Glu were performed. Finally, in vivo HERMES (20-ms editing pulses) and 1D J-resolved (TE 31-229 ms) experiments were performed on 137 participants using 3 T MRI scanners. LCModel was used for quantification. RESULTS: HERMES simulation and phantom experiments show a Glu-edited signal at 2.34 ppm in the Hadamard sum combination A+B+C+D with no overlapping Gln signal. The J-resolved simulations and phantom experiments show substantial TE modulation of the Glu and Gln signals across the TEs, whose average yields a well-resolved Glu signal closely matching the Glu-edited signal from the HERMES sum spectrum. In vivo quantification of Glu show that the two methods are highly correlated (p < 0.001) with a bias of ∼10%, along with similar between-subject coefficients of variation (HERMES/TE-averaged: ∼7.3%/∼6.9%). Other Hadamard combinations produce the expected GABA-edited (A+B-C-D) or GSH-edited (A-B+C-D) signal. CONCLUSION: HERMES simulation and phantom experiments show the separation of Glu from Gln. In vivo HERMES experiments yield Glu (without Gln), GABA, and GSH in a single MRS scan.


Assuntos
Ácido Glutâmico , Imageamento por Ressonância Magnética , Humanos , Espectroscopia de Ressonância Magnética/métodos , Glutamina , Glutationa/química , Ácido gama-Aminobutírico/química
5.
Addiction ; 118(12): 2384-2396, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37563863

RESUMO

AIMS: Prior studies showed that methamphetamine (METH) users had greater than normal age-related brain atrophy; whether having the apolipoprotein E (APOE)-ε4 allele may be a contributory factor has not been evaluated. We aimed to determine the independent and combined effects of chronic heavy METH use and having at least one copy of the APOE-ε4 allele (APOE-ε4+) on brain morphometry and cognition, especially in relation to aging. METHODS: We compared brain morphometry and cognitive performance in 77 individuals with chronic heavy METH use (26 APOE-ε4+, 51 APOE-ε4-) and 226 Non-METH users (66 APOE-ε4+, 160 APOE-ε4-), using a 2 × 2 design (two-way analysis of co-variance). Vertex-wise cortical volumes, thickness and seven subcortical volumes, were automatically measured using FreeSurfer. Linear regression between regional brain measures, and cognitive scores that showed group differences were evaluated. Group differences in age-related decline in brain and cognitive measures were also explored. RESULTS: Regardless of APOE-ε4 genotype, METH users had lower Motor Z-scores (P = 0.005), thinner right lateral-orbitofrontal cortices (P < 0.001), smaller left pars-triangularis gyrus volumes (P = 0.004), but larger pallida, hippocampi and amygdalae (P = 0.004-0.006) than nonusers. Across groups, APOE-ε4+ METH users had the smallest volumes of superior frontal cortical gyri bilaterally, and of the smallest volume in left rostral-middle frontal gyri (all P-values <0.001). Smaller right superior-frontal gyrus predicted poorer motor function only in APOE-ε4+ participants (interaction-P < 0.001). Cortical volumes and thickness declined with age similarly across all participants; however, APOE-ε4-carriers showed thinner right inferior parietal cortices than noncarriers at younger age (interaction-P < 0.001). CONCLUSIONS: Chronic heavy use and having at least one copy of the APOE-ε4 allele may have synergistic effects on brain atrophy, particularly in frontal cortices, which may contribute to their poorer cognitive function. However, the enlarged subcortical volumes in METH users replicated prior studies, and are likely due to METH-mediated neuroinflammation.


Assuntos
Metanfetamina , Humanos , Alelos , Metanfetamina/efeitos adversos , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cognição , Genótipo , Apolipoproteína E4/genética , Atrofia/patologia , Testes Neuropsicológicos
6.
J Infect Dis ; 228(11): 1559-1570, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37540098

RESUMO

BACKGROUND: The aim of this study was to determine whether neurometabolite abnormalities indicating neuroinflammation and neuronal injury are detectable in individuals post-coronavirus disease 2019 (COVID-19) with persistent neuropsychiatric symptoms. METHODS: All participants were studied with proton magnetic resonance spectroscopy at 3 T to assess neurometabolite concentrations (point-resolved spectroscopy, relaxation time/echo time = 3000/30 ms) in frontal white matter (FWM) and anterior cingulate cortex-gray matter (ACC-GM). Participants also completed the National Institutes of Health Toolbox cognition and motor batteries and selected modules from the Patient-Reported Outcomes Measurement Information System. RESULTS: Fifty-four participants were evaluated: 29 post-COVID-19 (mean ± SD age, 42.4 ± 12.3 years; approximately 8 months from COVID-19 diagnosis; 19 women) and 25 controls (age, 44.1 ± 12.3 years; 14 women). When compared with controls, the post-COVID-19 group had lower total N-acetyl compounds (tNAA; ACC-GM: -5.0%, P = .015; FWM: -4.4%, P = .13), FWM glutamate + glutamine (-9.5%, P = .001), and ACC-GM myo-inositol (-6.2%, P = .024). Additionally, only hospitalized patients post-COVID-19 showed age-related increases in myo-inositol, choline compounds, and total creatine (interaction P = .029 to <.001). Across all participants, lower FWM tNAA and higher ACC-GM myo-inositol predicted poorer performance on several cognitive measures (P = .001-.009), while lower ACC-GM tNAA predicted lower endurance on the 2-minute walk (P = .005). CONCLUSIONS: In participants post-COVID-19 with persistent neuropsychiatric symptoms, the lower-than-normal tNAA and glutamate + glutamine indicate neuronal injury, while the lower-than-normal myo-inositol reflects glial dysfunction, possibly related to mitochondrial dysfunction and oxidative stress in Post-COVID participants with persistent neuropsychiatric symptoms.


Assuntos
COVID-19 , Glutamina , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Espectroscopia de Prótons por Ressonância Magnética/métodos , Glutamina/metabolismo , Prótons , Teste para COVID-19 , COVID-19/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Inositol/metabolismo , Glutamatos/metabolismo , Ácido Aspártico/metabolismo
7.
NeuroImmune Pharm Ther ; 2(2): 89-94, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37476292

RESUMO

Objectives: Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 infection is associated with lower plasma glutathione (GSH) levels due to oxidative stress. However, plasma levels may not reflect brain GSH levels. Individuals with post-acute sequelae of COVID-19 (PASC) have a higher prevalence of cognitive fatigue, which might be related to altered brain γ-aminobutyric-acid (GABA) levels. Hence, our study aims to measure the brain GSH and GABA levels in PASC. Methods: 29 PASC participants and 24 uninfected controls were recruited for this study. Each was evaluated with detailed neuropsychiatric assessments and an edited proton MRS (Hadamard Encoding and Reconstruction of Mega-Edited Spectroscopy, HERMES) method to measure GABA and GSH concentrations in predominantly grey matter (GM) and predominantly white matter (WM) brain frontal voxels. Results: PASC participants were 219 ± 137 days since their COVID-19 diagnosis. Nine individuals with PASC were hospitalized. Compared to controls, individuals with PASC had similar levels of GABA in both brain regions, but lower GSH and greater age-related GSH decline in the frontal GM region. Conclusions: The lower-than-normal frontal GM GSH level in participants with PASC suggest that they have ongoing oxidative stress in the brain, and that older individuals may be even more vulnerable to oxidative stress.

8.
Neurology ; 100(23): e2409-e2423, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37185175

RESUMO

BACKGROUND AND OBJECTIVES: Post-COVID condition (PCC) is common and often involves neuropsychiatric symptoms. This study aimed to use blood oxygenation level-dependent fMRI (BOLD-fMRI) to assess whether participants with PCC had abnormal brain activation during working memory (WM) and whether the abnormal brain activation could predict cognitive performance, motor function, or psychiatric symptoms. METHODS: The participants with PCC had documented coronavirus disease 2019 (COVID-19) at least 6 weeks before enrollment. Healthy control participants had no prior history of COVID-19 and negative tests for severe acute respiratory syndrome coronavirus 2. Participants were assessed using 3 NIH Toolbox (NIHTB) batteries for Cognition (NIHTB-CB), Emotion (NIHTB-EB), and Motor function (NIHTB-MB) and selected tests from the Patient-Reported Outcomes Measurement Information System (PROMIS). Each had BOLD-fMRI at 3T, during WM (N-back) tasks with increasing attentional/WM load. RESULTS: One hundred sixty-nine participants were screened; 50 fulfilled the study criteria and had complete and usable data sets for this cross-sectional cohort study. Twenty-nine participants with PCC were diagnosed with COVID-19 242 ± 156 days earlier; they had similar ages (42 ± 12 vs 41 ± 12 years), gender proportion (65% vs 57%), racial/ethnic distribution, handedness, education, and socioeconomic status, as the 21 uninfected healthy controls. Despite the high prevalence of memory (79%) and concentration (93%) complaints, the PCC group had similar performance on the NIHTB-CB as the controls. However, participants with PCC had greater brain activation than the controls across the network (false discovery rate-corrected p = 0.003, Tmax = 4.17), with greater activation in the right superior frontal gyrus (p = 0.009, Cohen d = 0.81, 95% CI 0.15-1.46) but lesser deactivation in the default mode regions (p = 0.001, d = 1.03, 95% CI 0.61-1.99). Compared with controls, participants with PCC also had poorer dexterity and endurance on the NIHTB-MB, higher T scores for negative affect and perceived stress, but lower T scores for psychological well-being on the NIHTB-EB, as well as more pain symptoms and poorer mental and physical health on measures from the PROMIS. Greater brain activation predicted poorer scores on measures that were abnormal on the NIHTB-EB. DISCUSSION: Participants with PCC and neuropsychiatric symptoms demonstrated compensatory neural processes with greater usage of alternate brain regions, and reorganized networks, to maintain normal performance during WM tasks. BOLD-fMRI was sensitive for detecting brain abnormalities that correlated with various quantitative neuropsychiatric symptoms.


Assuntos
COVID-19 , Memória de Curto Prazo , Humanos , Memória de Curto Prazo/fisiologia , Síndrome de COVID-19 Pós-Aguda , Estudos Transversais , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Testes Neuropsicológicos
9.
NeuroImmune Pharm Ther ; 2(1): 37-48, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37067870

RESUMO

Objectives: We aimed to compare brain white matter integrity in participants with post-COVID-19 conditions (PCC) and healthy controls. Methods: We compared cognitive performance (NIH Toolbox®), psychiatric symptoms and diffusion tensor imaging (DTI) metrics between 23 PCC participants and 24 controls. Fractional anisotropy (FA), axial (AD), radial (RD), and mean (MD) diffusivities were measured in 9 white matter tracts and 6 subcortical regions using MRICloud. Results: Compared to controls, PCC had similar cognitive performance, but greater psychiatric symptoms and perceived stress, as well as higher FA and lower diffusivities in multiple white matter tracts (ANCOVA-p-values≤0.001-0.048). Amongst women, PCC had higher left amygdala-MD than controls (sex-by-PCC p=0.006). Regardless of COVID-19 history, higher sagittal strata-FA predicted greater fatigue (r=0.48-0.52, p<0.001) in all participants, and higher left amygdala-MD predicted greater fatigue (r=0.61, p<0.001) and anxiety (r=0.69, p<0.001) in women, and higher perceived stress (r=0.45, p=0.002) for all participants. Conclusions: Microstructural abnormalities are evident in PCC participants averaged six months after COVID-19. The restricted diffusivity (with reduced MD) and higher FA suggest enhanced myelination or increased magnetic susceptibility from iron deposition, as seen in stress conditions. The higher amygdala-MD in female PCC suggests persistent neuroinflammation, which might contribute to their fatigue, anxiety, and perceived stress.

10.
Pediatr Res ; 94(1): 356-364, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36456690

RESUMO

BACKGROUND: The aim of this study was to determine the extent to which socioeconomic characteristics of the home and neighborhood are associated with racial inequalities in brain outcomes. METHODS: We performed a cross-sectional analysis of the baseline dataset (v.2.0.1) from the Adolescent Brain and Cognitive Development (ABCD) Study. Cognitive performance was assessed using the National Institutes of Health Toolbox (NIH-TB) cognitive battery. Standard socioeconomic indicators of the family and neighborhood were derived from census-related statistics. Cortical morphometric measures included MRI-derived thickness, area, and volume. RESULTS: 9638 children were included. Each NIH-TB cognitive measure was negatively associated with household and neighborhood socioeconomic characteristics. Differences in cognitive scores between Black or Hispanic children and other racial groups were mitigated by higher household income. Most children from lowest-income families or residents in impoverished neighborhoods were Black or Hispanic. These disparities were associated with racial differences in NIH-TB measures and mediated by smaller cortical brain volumes. CONCLUSIONS: Neighborhood socioeconomic characteristics are associated with racial differences in preadolescent brain outcomes and mitigated by greater household income. Household income mediates racial differences more strongly than neighborhood-level socioeconomic indicators in brain outcomes. Highlighting these socioeconomic risks may direct focused policy-based interventions such as allocation of community resources to ensure equitable brain outcomes in children. IMPACT: Neighborhood socioeconomic characteristics are associated with racial differences in preadolescent brain outcomes and mitigated by greater household income. Household income mediates racial differences more strongly than neighborhood-level socioeconomic indicators in brain outcomes. Highlighting these disparities related to socioeconomic risks may direct focused policy-based interventions such as allocation of community resources to ensure equitable brain outcomes in children.


Assuntos
Pobreza , Grupos Raciais , Criança , Adolescente , Humanos , Estudos Transversais , Fatores Socioeconômicos , Características de Residência , Encéfalo/diagnóstico por imagem
12.
Rev Sci Instrum ; 93(10): 103502, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319339

RESUMO

Mesoscale imperfections, such as pores and voids, can strongly modify the properties and the mechanical response of materials under extreme conditions. Tracking the material response and microstructure evolution during void collapse is crucial for understanding its performance. In particular, imperfections in the ablator materials, such as voids, can limit the efficiency of the fusion reaction and ultimately hinder ignition. To characterize how voids influence the response of materials during dynamic loading and seed hydrodynamic instabilities, we have developed a tailored fabrication procedure for designer targets with voids at specific locations. Our procedure uses SU-8 as a proxy for the ablator materials and hollow silica microspheres as a proxy for voids and pores. By using photolithography to design the targets' geometry, we demonstrate precise and highly reproducible placement of a single void within the sample, which is key for a detailed understanding of its behavior under shock compression. This fabrication technique will benefit high-repetition rate experiments at x-ray and laser facilities. Insight from shock compression experiments will provide benchmarks for the next generation of microphysics modeling.

13.
Opt Express ; 30(21): 38405-38422, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36258406

RESUMO

Inertial confinement fusion (ICF) holds increasing promise as a potential source of abundant, clean energy, but has been impeded by defects such as micro-voids in the ablator layer of the fuel capsules. It is critical to understand how these micro-voids interact with the laser-driven shock waves that compress the fuel pellet. At the Matter in Extreme Conditions (MEC) instrument at the Linac Coherent Light Source (LCLS), we utilized an x-ray pulse train with ns separation, an x-ray microscope, and an ultrafast x-ray imaging (UXI) detector to image shock wave interactions with micro-voids. To minimize the high- and low-frequency variations of the captured images, we incorporated principal component analysis (PCA) and image alignment for flat-field correction. After applying these techniques we generated phase and attenuation maps from a 2D hydrodynamic radiation code (xRAGE), which were used to simulate XPCI images that we qualitatively compare with experimental images, providing a one-to-one comparison for benchmarking material performance. Moreover, we implement a transport-of-intensity (TIE) based method to obtain the average projected mass density (areal density) of our experimental images, yielding insight into how defect-bearing ablator materials alter microstructural feature evolution, material compression, and shock wave propagation on ICF-relevant time scales.

14.
Pediatr Dermatol ; 39(2): 326-327, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35118710

RESUMO

We present three children with tinea incognito initially misdiagnosed as allergic contact dermatitis to face masks. All three patients presented with pruritic erythematous patches and plaques across the malar cheek and nose. This case series suggests that clinicians should keep a broad differential when evaluating mask-related facial dermatoses in children.


Assuntos
COVID-19 , Dermatite Alérgica de Contato , Dermatoses Faciais , Tinha , Criança , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/etiologia , Dermatoses Faciais/diagnóstico , Dermatoses Faciais/etiologia , Humanos , Tinha/diagnóstico , Tinha/tratamento farmacológico
15.
AIDS ; 36(4): 513-524, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-34860196

RESUMO

OBJECTIVES: Tobacco smoking is linked to cognitive deficits and greater white matter (WM) abnormalities in people with HIV disease (PWH). Whether tobacco smoking additionally contributes to brain atrophy in PWH is unknown and was evaluated in this study. DESIGN: We used a 2 × 2 design that included 83 PWH (43 nonsmokers, 40 smokers) and 171 HIV-seronegative (SN, 106 nonsmokers, 65 smokers) participants and assessed their brain structure and cognitive function. METHODS: Selected subcortical volumes, voxel-wise cortical volumes and thickness, and total WM volume were analyzed using FreeSurfer. Independent and interactive effects of HIV and smoking were evaluated with two-way analysis of covariance on cognitive domain Z-scores and morphometric measures on T1-weighted MRI. RESULTS: Regardless of smoking status, relative to SN, PWH had smaller brain volumes [basal ganglia, thalami, hippocampi, subcortical gray matter (GM) and cerebral WM volumes (P = 0.002-0.042)], steeper age-related declines in the right superior-parietal (interaction: P < 0.001) volumes, and poorer attention/working memory and learning (P = 0.016-0.027). Regardless of HIV serostatus, smokers tended to have smaller hippocampi than nonsmokers (-0.6%, P = 0.055). PWH smokers had the smallest total and regional subcortical GM and cortical WM volume and poorest cognitive performance. CONCLUSIONS: Tobacco smoking additionally contributed to brain atrophy and cognitive deficits in PWH. The greater brain atrophy in PWH smokers may be due to greater neuronal damage or myelin loss in various brain regions, leading to their poor cognitive performance. Therefore, tobacco smoking may exacerbate or increase the risk for HIV-associated neurocognitive disorders.


Assuntos
Doenças do Sistema Nervoso Central , Infecções por HIV , Doenças Neurodegenerativas , Atrofia/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Doenças do Sistema Nervoso Central/patologia , Cognição , Infecções por HIV/patologia , Humanos , Imageamento por Ressonância Magnética , Doenças Neurodegenerativas/patologia , Fumar Tabaco/efeitos adversos
16.
J Neuroimmune Pharmacol ; 16(2): 334-345, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32323137

RESUMO

AIMS: Cognitive impairment may be greater in HIV-positive (HIV+) women than in HIV+ men. Whether sex-specific differences exist in brain microstructure of HIV+ individuals is unknown and was evaluated. METHOD: 39 HIV+ (21 men, 18 women) and 45 seronegative (SN, 20 men, 25 women) participants were assessed with brain diffusion tensor imaging and cognitive assessments (7 neuropsychological domains). Fractional anisotropy (FA) and mean diffusivity (MD) were measured with an automated atlas in selected brain regions. Group comparisons were assessed with linear mixed effects models, with sub-regions and hemisphere (left/right) as repeated factors for each region. RESULTS: HIV+ women, but not HIV+ men, were slower than sex-matched SN controls on sensorimotor function (Dominant-hand: interaction-p = 0.007; Non-dominant hand: interaction-p = 0.039). Similarly, only HIV+ women had lower FA in the globus pallidus (GP, interaction-p = 0.011). Additionally, regardless of sex, the HIV+ group had poorer Fluency, Speed, and Attention than SN-controls (p = 0.006-0.008), as well as lower FA and higher MD in multiple brain regions (p = <0.001-0.044). Across all participants, performance on Attention was predicted by uncinate-FA (p < 0.001, r = 0.5) and corpus callosum (CC)-FA (p = 0.038, r = 0.23), while the Speed of Information Processing was predicted by CC-FA (p = 0.009, r = 0.3). Furthermore, faster sensorimotor function correlated with higher CC-FA and uncinate-FA in men but not in women (Sex*DTI-interaction-p = 0.03-0.06). CONCLUSIONS: The relatively poorer sensorimotor function and abnormally lower GP_FA, suggesting lesser neuronal integrity, in HIV+ women demonstrate sex-specific effects from HIV-infection on these measures. These findings may be related to the greater immune activation and neuroinflammation in HIV+ women compared to HIV+ men. Graphical Abstract.


Assuntos
Complexo AIDS Demência/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Globo Pálido/fisiopatologia , Caracteres Sexuais , Adulto , Anisotropia , Disfunção Cognitiva/virologia , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Sci Transl Med ; 12(563)2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32998969

RESUMO

Recent genome-wide association studies identified the angiotensin-converting enzyme gene (ACE) as an Alzheimer's disease (AD) risk locus. However, the pathogenic mechanism by which ACE causes AD is unknown. Using whole-genome sequencing, we identified rare ACE coding variants in AD families and investigated one, ACE1 R1279Q, in knockin (KI) mice. Similar to AD, ACE1 was increased in neurons, but not microglia or astrocytes, of KI brains, which became elevated further with age. Angiotensin II (angII) and angII receptor AT1R signaling were also increased in KI brains. Autosomal dominant neurodegeneration and neuroinflammation occurred with aging in KI hippocampus, which were absent in the cortex and cerebellum. Female KI mice exhibited greater hippocampal electroencephalograph disruption and memory impairment compared to males. ACE variant effects were more pronounced in female KI mice, suggesting a mechanism for higher AD risk in women. Hippocampal neurodegeneration was completely rescued by treatment with brain-penetrant drugs that inhibit ACE1 and AT1R. Although ACE variant-induced neurodegeneration did not depend on ß-amyloid (Aß) pathology, amyloidosis in 5XFAD mice crossed to KI mice accelerated neurodegeneration and neuroinflammation, whereas Aß deposition was unchanged. KI mice had normal blood pressure and cerebrovascular functions. Our findings strongly suggest that increased ACE1/angII signaling causes aging-dependent, Aß-accelerated selective hippocampal neuron vulnerability and female susceptibility, hallmarks of AD that have hitherto been enigmatic. We conclude that repurposed brain-penetrant ACE inhibitors and AT1R blockers may protect against AD.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Feminino , Estudo de Associação Genômica Ampla , Masculino , Camundongos , Camundongos Transgênicos
18.
Sci Rep ; 10(1): 10197, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32576908

RESUMO

SiO2 is one of the most fundamental constituents in planetary bodies, being an essential building block of major mineral phases in the crust and mantle of terrestrial planets (1-10 ME). Silica at depths greater than 300 km may be present in the form of the rutile-type, high pressure polymorph stishovite (P42/mnm) and its thermodynamic stability is of great interest for understanding the seismic and dynamic structure of planetary interiors. Previous studies on stishovite via static and dynamic (shock) compression techniques are contradictory and the observed differences in the lattice-level response is still not clearly understood. Here, laser-induced shock compression experiments at the LCLS- and SACLA XFEL light-sources elucidate the high-pressure behavior of stishovite on the lattice-level under in situ conditions on the Hugoniot to pressures above 300 GPa. We find stishovite is still (meta-)stable at these conditions, and does not undergo any phase transitions. This contradicts static experiments showing structural transformations to the CaCl2, α-PbO2 and pyrite-type structures. However, rate-limited kinetic hindrance may explain our observations. These results are important to our understanding into the validity of EOS data from nanosecond experiments for geophysical applications.

19.
Addict Behav ; 110: 106489, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32563021

RESUMO

AIMS: People who have experienced adverse childhood experiences (ACEs) are more susceptible to substance use disorder (SUD) and depression. The present study examined depression prevalence in hospitalized patients with SUD and examined the association of individual ACEs with major depression. Depression rates 3 months after discharge were also examined. METHODS: Medical inpatients with SUD were recruited from Temple University Hospital. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9) at baseline and 3 months post-discharge. Participants were also assessed using an ACE scale at baseline. RESULTS: Of 79 baseline participants, 48% (38) had moderate to severe major depressive disorder (MDD) with PHQ-9 scores ≥15. Among those with baseline MDD, 38% (9/24) continued to have MDD 3 months post discharge, and 42.9% (12/28) of those without MDD at baseline met criteria at 3 months. Sixty-three percent (50/79) of the participants reported 4+ ACEs at baseline. Two ACEs, Household Incarceration and Household Mental Illness, were significantly associated with having MDD at baseline and 3 months (adjusted mean PHQ-9 total score increase (SE) and p-value: 2.97 (1.35), p < .05; 5.32 (1.37), p < .005, respectively). CONCLUSIONS: In this exploratory study, nearly half of medical inpatients with substance use disorder had moderate to severe major depression, with a similar percentage of participants having MDD as outpatients at 3 months. Approximately two thirds of participants reported four or more adverse childhood experiences at baseline. Inpatient medical hospitalization should be utilized as an opportunity to engage people with SUD in multidisciplinary treatment including psychiatric, trauma informed care, and substance abuse treatment.


Assuntos
Experiências Adversas da Infância , Transtorno Depressivo Maior , Transtornos Relacionados ao Uso de Substâncias , Assistência ao Convalescente , Criança , Depressão , Transtorno Depressivo Maior/epidemiologia , Hospitalização , Humanos , Alta do Paciente , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
20.
Opt Lett ; 44(3): 530-533, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30702671

RESUMO

We analyze the crystal orientation-dependent polarization state of extreme ultraviolet high-order harmonics from bulk magnesium oxide crystals subjected to intense linearly polarized laser fields. We find that only along high-symmetry directions do high-order harmonics follow the polarization direction of the laser field. In general, there are strong deviations that depend on harmonic order, strength of the laser field, and crystal orientation. We use a real-space electron trajectory picture to understand the origin of polarization deviations. These results have implications in all-optical probing of electronic band structure in momentum space and valence charge distributions in real space, and in producing attosecond pulses with time-dependent polarization in compact setups.

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